Extech Instruments Extech HD755 User manual

UserManual



HeavyDuty

DifferentialPressureManometer



ModelHD755



HD755-en-GB_V1.8 9/16

Introduction

CongratulationsonyourpurchaseoftheExtechManometerModelHD755.Thisdevicemeasures

gaugeanddifferentialpressureintherangeof±0.500psi.TheHD755offerseleven(11)unitsof

measure(userselectablebyfrontpanelpushbutton)andhasadifferentialinputthatuses

convenientquick‐disconnectfittings.AdvancedfeaturesincludeDATAHOLD,MIN‐MAX‐AVG

RECORDmode,ZERO/OFFSET,AUTOPOWEROFF,andUSBPCinterface.Thismeterisshippedfully

testedandcalibratedand,withproperuse,willprovideyearsofreliableservice.Pleasevisitour

website(www.extech.com)tocheckforthelatestversionofthisUserGuide,ProductUpdates,

and

CustomerSupport.



MeterDescription

1. P1input

2. ACadaptorjack

3. P2Input

4. LCDDisplay–Indicatesthemeasurementdata,unitofmeasure,

elapsedtimer,andfunctionsymbolsasdescribedinthismanual

5. USBPCinterfacejack(3.5mm)–Forusewithdataacquisition

software

6. UNITbutton–Presstoselect

theunitofmeasure

7. DIFbutton–Presstodisplaydifferentialpressure.Alsousedto

OFFSETthedisplayedreadings.

8. RECORDbutton–PresstoaccesstheMIN/MAX/AVGrecording

mode

9. HOLD/ZERObutton–Presstofreezethedisplayedreading.Also

usedtozerothedisplay(pressandholduntil

displayshowsallzeroes).

10. BACKLIGHT

button–Presstoswitchthe displaybacklightON.Thebacklightwill

automaticallyturnOFFafter40seconds.

11. POWERbutton–PresstoturnthemeterONorOFF

12. Batterycompartment(onrear)



HD755-en-GB_V1.8 9/16

Display

1. USBdataoutputactive

2. DifferentialPressureMode

3. DataHoldMode

4. Primarydisplay

5. RecordMode

6. MAX/MIN/AVGindicators

7. LowBatteryIndicator

8. Pressureunitofmeasure

9. ElapsedTimer

HD755-en-GB_V1.8 9/16

BasicOperation

MeterPower

TheHD755usesa9Vbatteryforpower.IfthemeterdoesnotswitchonwhenthePOWER

buttonispressedorifthedisplayshowsBAT,replacethebattery.

WhenthePOWERbuttonsispressed,themeterperformsashortself‐testandrevertstothe

settingsinplace

whenthemeterwaslastturnedoff.

AutomaticPower‐offFeature

Inordertoconservebatterylife,themeterhasanautomaticpowerofffeature(after20

minutes).Todefeatthisfeature,pressandholdtheHOLDbuttonwhileturningthemeteron.

ReleasetheHOLDbuttonwhen‘n’appearsonthedisplay.Themeterwillnowremainonuntil

theuserturnsitofforuntilthebatteryweakens.NotethattheAutoPowerOFFfeaturewillbe

reactivatedthenexttimethemeteristurnedoffandthenon.

UnitofMeasure

PresstheUNITbuttontoselecttheunitofmeasure.Thismeterofferseleven(11)unitsof

measureaslistedbelow.



UnitofMeasure Displayicon

Poundspersquareinch psi

InchesofMercury inHg

Milli‐bar mbar

MillimetersofMercury mmHg

Kilo‐Pascals kPa

Kilogramspercentimetersquared Kgcm



Inchesofwater inH

O

Feetofwater ftH

O

Centimetersofwater cmH

O

Bars Bar

Ouncespersquareinch ozin



FittingsConnection

ConnecttubingtotheP1,P2(orboth)inputport(s).Ifbothinputsareused(differentialmode),

themeterdisplaysapositivepressurereadingiftheP1pressureisgreaterthanP2anda

negativereadingifP2isgreaterthanP1.



HD755-en-GB_V1.8 9/16

ZeroAdjustandOffsetfunction

TheunitmustbekeptintheuprightpositionwhenZEROINGorwhentakingmeasurements.To

ZEROthemeter:Beforeuseandwithoutfittingsattachedtothemeter,pressandholdtheHOLD

buttonfor3secondsoruntilthedisplayshowsallzeroes.



ToOFFSETmeterreadings:Pressthe

DIFbuttonwhiletakingameasurement.Subsequent

readingswillrepresentthedifferencebetweenthecurrentmeasurementandthemeasurement

thatwasonthedisplaywhentheDIFbuttonwaspressed..PresstheDIFbuttonagaintoexitthe

OFFSETfunction.

MIN‐MAX‐AVGModewithElapsedTimer

TheRECORDfunctionrecordsasinglemaximum(MAX),minimum(MIN),andaverage(AVG)

readingswithatimestamp.Theelapsedtimerisdisplayedonthelowerright‐handcornerofthe

LCDandinformstheuserofthetimeaMAXorMINreadingwasrecorded.

1. PresstheRECORDbutton once.TheRECindicatorwillappearonthedisplayandthe

displayedelapsedtimerwillstart(HH:MM:SSformat[hours:minutes:seconds]).

2. PresstheRECORDbutton againtoviewthehighest(MAX)reading

recordedsincethe

RECORDbuttonwasfirstpressed.TheMAXindicatorandmaximumreadingwillappearon

thedisplay.TheelapsedtimerwillshowthetimeoftheMAXevent.

3. PresstheRECORDbutton again,theMINindicatorandtheminimumvaluewillappearon

thedisplay.Theelapsed

timerwillshowthetimeoftheMINevent.

4. PresstheRECORDbutton again,theAVGindicatorandtheaveragevaluewillappearonthe

display.Theelapsedtimerwillcontinuetorun.

5. Toreturntonormaloperation,pressandholdtheRECORDbuttonuntilthedisplay

indicatorsREC,MAX,etc.switchoff.

NotethatintheRECORDmode,thebacklightandthepowerbuttonsaretheonlyavailable

functions.TheMin,Max,andAVGdatacannotbeexportedtothePC.

PCInterface

Themeterhasabuilt‐inUSBportforusewiththeManometerDataAcquisitionsoftware.The

softwareallowstheusertoview,recordandprintreadingsfromtheHD755whileitisconnected

directlytoaPC.Refertothedocumentationincludedwiththesoftwareforcompletedetails.

DisplayedErrorCodes

Thefollowingcodesaredisplayedwhenthemeterencountersanerror.

ERR1:Pressureinputexceedsspecifiedlimits

ERR2:Pressureinputistoolowtoread

ERR3:TheDifferentialPressureinputexceedsspecifiedlimits

ERR4:TheDifferentialPressureinputistoolowtoread

HD755-en-GB_V1.8 9/16

Specifications

GeneralSpecifications

Display FourdigitLCDwithfunctionindicators

UnitsofMeasure BAR,mBAR,psi,kg/cm

,mmHg,inchesHg,kPa,feetH

O,inches

O,cmH

O,andozin

2

Accuracy ±0.3%FS+1d(@25°C)

Repeatability ±0.2%to0.5%FS

Linearity/Hysteresis ±0.3%FS

CombinedAccuracy ±1.1%FS

MaximumPressure 2psi

Responsetime 0.5stypical

Inputcircuit Differentialinputs(P1andP2)

InputPorts Twometal4.8mm,barbedfor1/8"(3.17mm)IDtubing

DataHold Freezesdisplayedreading

Sensor Built‐inpiezoelectricsensors



Zero/Offsetfunction Pushbuttonactivation

Samplerate 0.5sec.(approx.)

Compatibility Airornon‐corrosiveandnon‐ionizedgas (notintended forusewith

liquids)

AutoPowerOFF Meterturnsoffafterapprox.20minutestoconserveenergy(can

bedeactivated)

PCInterface Built‐inUSBserialinterface

Storage

conditions 0to60

C(14to140

F);<80%RH

Operatingconditions 0to50

C(32to122

F);<80%RH

Batterypower 9Valkalinebattery(BATlowbatteryindicator)

Batterylife 125hourstypical

Dimensions 210x75x50mm(8.2x2.9x1.9”)

Weight 280g(9.8oz)

HD755-en-GB_V1.8 9/16

RangeSpecifications

Range/Units(Max.) Resolution

±0.034bar 0.001

±34.47mbar 0.01

±0.500psi 0.001

±0.035Kg/cm

 0.001

±25.86mmHg 0.01

±1.018inchesHg 0.001

±3.447kPa 0.001

±1.154feetH

O 0.001

±13.85inchesH

O 0.01

±35.15cmH

O 0.01

±8.00ozin

 0.01



BatteryReplacement

WhenthelowbatteryindicatorBATappearsonthedisplayorifthemeterdoesnotswitchon

whenthePOWERbuttonispressed,itisnecessarytoreplacethebattery.

Toreplacethebattery:

1. Openthebatterycompartmentbyslidingthemeter’srearpanelinthedirectionofthe

embossedarrow.

2. Replacethe9Valkalinebattery

3. Replacethebatterycompartmentcover.



Neverdisposeofusedbatteriesorrechargeablebatteriesinhouseholdwaste.

Asconsumers,usersarelegallyrequiredtotakeusedbatteriestoappropriatecollection

sites,theretailstorewherethebatterieswerepurchased,orwhereverbatteries

aresold.

Disposal:Donotdisposeofthisinstrumentinhouseholdwaste.Theuserisobligatedto

takeend‐of‐lifedevicestoadesignatedcollectionpointforthedisposalofelectricaland

electronicequipment.



OtherBatterySafetyReminders

 Neverdisposeofbatteriesinafire.Batteriesmayexplodeorleak.

 Nevermixbatterytypes.Alwaysinstallnewbatteriesofthesametype.



Warning: Pressure inputs of 10 psi or higher will damage the instrument. Do not

apply pressure higher than the maximum pressure listed in the specification table

HD755-en-GB_V1.8 9/16

Conversions

UsefulconversionFactors

From To Multiplier

inofH

O inofHg 0.07355

inofH

O cmofH

O 2.54

mmofHg inofH

O 0.03937



Allrightsreservedincludingtherightofreproductioninwholeorinpartinanyform

ISO‐9001Certified

www.extech.com



Extech Instruments Extech HD755, HD755 User manual

Related papers

Other documents